Why the "trailing" woodpecker sound? I recently (March 26th, 2022) recorded a woodpecker in the woods around Habo Ljunga, Lomma, Skåne, Sweden and that gave me an idea. While cutting the audio, I noticed that the woodpecker's sound seems to have two moments (see waveform below): a main one (gray) and a trailing one (light blue). **Does anyone know why the sound trails off?** I made several recordings and at least my subject woodpecker consistently features these two moments. If helpful, here is the original video showing the movement of the woodpecker. ![Woodpecker's sound waveform](

in the UK we have two species of woodpecker that use drumming for communication. One of these - the greater spotted woodpecker - tails off at the end of the sequence as it gradually slows and eases pressure. The other species - lesser spotted woodpecker - stops much more abruptly, without this tailing off. The difference between the two patterns allows you to determine which species you are listening to.

For examples of each, you can check out XenoCanto recordings here:
Greater: <
Lesser: <